Patients with sarcomas are studied for evidence of serum reactivity against tumor-associated determinants expressed on both fresh and cultured syngeneic and allogeneic tumor cells using immunofluorescence and immunoperoxidase staining techniques. An experimental model of pancreatic carcinoma has been developed in hamsters. Tumor-associated antigens have been isolated from both animal and human pancreatic cancers and are being investigated for possible applications to immunotherapy or methods of immunodiagnosis. Tissue-specific antigens have been isolated and are being investigated for possible use in immunotherapy of pancreatic carcinoma. Intraoperative radiotherapy is evaluated in dogs to determine responses of both normal and surgically-manipulated tissues to direct single-dose electron-beam irradiation in approaches to adapt operative radiotherapy to the treatment of human abdominal malignancies.